How do I find slope in a graph ?!

slope = rise / run  =  (vertical leg length)/(horizontal leg length)

Step-by-step explanation:

This is a very general question.

The best way is to think of the line as the hypotenuse of a right triangle.

where the endpoints of this hypotenuse are the 2 points on the line.

so   the slope = ( length of vertical leg of triangle) / (horizontal length of triangle)

for example if the two points  were  (1, 0)  and  (3, 5)

then   the vertical length of leg =  (5 - 0) = 5

and the horizontal length of leg = (3 - 1) = 2

so.  the slope =  5/2

X+12=20 is 8.

x-9=17 and 2x=16 both have the same solution.

The answer should be X+12=20.